<html xmlns="http://www.w3.org/1999/xhtml">

<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>JSONP方式</title>
    <script type="text/javascript" src="/js/jquery-1.5.1.min.js"></script>
</head>

<body>
    <textarea id="message">这是员工的密码！</textarea><br />
    <button id="test">看看领导在说什么</button><br />
    <script>
        document.getElementById("test").onclick = function () {
            alert(parent.document.getElementById("message").value);
        }
    </script>
</body>

</html>